Clamp tightening device for clamp carrier



Jan. 6, 1970 QUICK ET AL CLAMP TIGHTENING DEVICE FOR CLAMP CARRIER 2 Sheet 1 Filed Dec.

Lfoy ck 'jbzl flzdrfp I B) 6M TTORNEY Jan. 6, 1970 QUICK ET AL CLAMP TIGH'IENING DEVICE FOR CLAMP CARRIER 2 Sheets-Sheet 2 Filed Dec. 19, 196'? Lfay Quack JQMQTZ'BZ 'ATTORNEY United States Patent 3,488,046 CLAMP TIGHTENING DEVICE FOR CLAMP CARRIER Lloyd Quick and John L. Mortoly, Poughkeepsre, N.Y., assiguors to James L. Taylor Manufacturing Company, Poughkeepsie, N.Y., a corporation of New Jersey Filed Dec. 19, 1967, Ser. No. 691,803

Int. Cl. B25b 5/06 US. Cl. 26920 11 Claims ABSTRACT OF THE DISCLOSURE The housing of a fluid pressure rotary air motor is mounted for limited relative rotation on a support which is movable selectively to cause engagement and disengagement of a driving member on the motor shaft respectively with and from an operating element for the movable jaw of any of a plurality of clamps in a row. Said jaw is mounted on a rigid frame, and a reaction member is rigidly connected to the motor housing and engageable and disengageable with and from said rigid frame simultaneously with said engagement and disengagement of said driving member with said operating element, respectively, to prevent twisting of the clamp.

BACKGROUND OF THE INVENTION Field of the invention The present invention relates to the tightening of clamps by means of torque developing apparatus. More particularly, the present invention is directed to the prevention of the twisting of clamps during the tightening process and, more particularly, to apparatus which may be quickly, positively and serially engaged with a plura ity of clamps and which, when energized, will not cause overtightening of the clamps. Accordingly, the general objects of the present invention are to provide novel and improved methods and apparatus of such character.

Description of the prior art While not limited thereto in its utility, the present invention has been found to be particularly well suited for use with and thus is shown in the environment of a clamp carrier having a plurality of clamps which are employed to hold sandwiched structures of wood material during an operation such as gluing. Examples of this type of clamp carrier may be found in US. Patent Nos. 1,653,035 and 1,702,036, both issued to R. W. Burns. A disclosure of an individual clamp which clearly shows the prior art mode of manual adjustment of the clamp jaws may be found in US. Patent No. 1,529,281 to J. L. Taylor.

In the clamping of materials which are susceptible to undesirable distortion and/ or breakage, the prior art has been plagued with problems. These problems include the difliculty of sufiiciently clamping the work without applying undue force thereto and while simultaneously preventing twisting of the clamp with its coincident distortion of the work. Due to these problems, the clamping operation in a continuing process of, for example, preparing pieces for use in furniture has usually been performed by hand. Attempts have been made to employ blind pressureoperated impact or other torque developing wrenches in order to speed up the clamping operation. However, impact wrenches have been characterized by excessive maintenance and, unless the workman was particularly skillful and careful in controlling the wrench, the clamp and work was often damaged through the application of excessive clamping force. Prior attempts to use other torque wrenches, in addition to the problems encountered in the use of impact wrenches, have also been characterized by 3,488,046 Patented Jan. 6, 1970 ice SUMMARY OF THE INVENTION The present invention overcomes the above-discussed disadvantages of the prior art and, in so doing, provides apparatus for tightening and/or loosening clamps wherein the problems of overtightening and clamp twisting are eliminated. To accomplish the foregoing, the present invention employs a reversible air motor with gear reduction which may be adjusted to develop a desired clamping torque. The motor has a driving member for the operating element of the clamp and will thus tighten the clamp until the preselected clamping pressure is reached at which time the motor will stall, and a reaction member on the motor housing engages the clamp frame, which prevents twisting of the clamp or damage to the work. In the environment of a clamp carrier, the air motor is mounted on a bracket which is slidable horizontally along the ends of clamps that are horizontally spaced apart in a common plane. The motor and a portion of the slidable bracket are rotatable longitudinally of the clamps to facilitate engagement of the driving member and reaction member with the individual clamps.

BRIEF DESCRIPTION OF THE DRAWING The present invention may be better understood and its numerous advantages will become apparent to those skilled in the art by reference to the accompanying drawing wherein like reference numerals refer to like elements in the various figures and in which:

FIGURE 1 is a side elevation view of a preferred embodiment of the present invention installed on a clamp carrier, the carrier being partially depicted.

FIGURE 2 is a top view, taken along line 2-2 of FIG- URE 1, of the embodiment of FIGURE 1.

FIGURE 3 is an enlarged side elevation view of the preferred embodiment of FIGURE 1.

FIGURE 4 is an enlarged top view of the preferred em bodiment of FIGURE 1.

FIGURE 5 is a cross-sectional view taken along line 5-5 of FIGURE 2, of a portion of one of the clamps of the clamp carrier shown partially in FIGURE 1.

FIGURE 6 is an end view, taken along line 6-6 of IFJIGURE 3, of one of the clamps of the carrier of FIG- FIGURE 7 is an end view, taken along line 7-7 of FIGURE 3, showing the clamp engaging end of the preferred embodiment of the present invention partially in section.

FIGURE 8 is a view, taken along line 8-8 of FIG- URE 4, showing the outwardly disposed end of the prefered embodiment of the present invention.

FIGURE 9 is aside view, taken along line 9-9 of FIGURE 4, depicting partially in section the mating of the clamping torque developing motor of the present invention with its mounting bracket.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIGURE 1, a clamp carrier of the general type of that shown in one of the above-mentioned patents to Burns is indicated generally at 10. Clamp carrier 10 comprises a plurality of clamps arranged in rows transversely of the carrier, the individual clamps being indicated generally at 12. As may be seen from FIGURE 2, there may be four or more clamps in a row of clamps on a carrier. The clamps are advanced by the carrier, in a clockwise direction in FIGURE 1, and the carrier will be stopped when clamps in a row rest on the top of a horizontal support bar 14 with the ends of the clamps in a common plane. Bar 14 is in turn supported from the floor or clamp carrier base by means of a pair of legs, only one of which 16 is shown. When it is desired to advance a group of laterally aligned clamps past the support bar 14, legs 16 are pivoted about pivot point 18, in a direction away from the clamp carrier, by means of a fluid operated piston 20 and actuating rod 22.

As may best be seen from FIGURE 1, each of clamps 12 has a pair of jaws 24 and 26, jaws 24 being adjustable and jaws 26 being fixed. The clamps 12 will typically be screw clamps of the same general type as shown in the above-mentioned Taylor patent. As may best be seen from FIGURE 5, each of clamps 12 has a rotating member, indicated generally at 28, which extends outwardly past the fixed jaw 26. The rotating operating member 28 of each screw clamp 12 threadably engages a draw bar assembly 30a which is connected to the movable jaw of the clamp 24. Thus, by driving the member 28 of the clamp in the proper direction, the adjustable jaw 24 may be caused to move toward or away from the stationary jaw 26. As may be seen from a joint consideration of FIGURES 2 and 5, each rotating operating member 28 has a cylindrical center portion and a pair of wings 3030 extending from opposite sides of the center portion. As will be discussed in detail below, the driving member of the motor employed to adjust the clamps is designed for engagement with the wings 3030 on the rotating members 28 of the screw clamps 12.

In accordance with the present invention, the means for adjusting clamps 12 comprises an air motor 32 having a driving member 34 on its shaft, and a talk reaction member 36 associated therewith. These members may be seen most clearly from FIGURES 3 and 4. As may be seen from FIGURE 1, the air motor and its associated components are mounted from rotatable legs 16 by means of a frame indicated generally at 38. Referring again to FIG- URE 3, the motor support frame comprises a pair of parallel, U-shaped channels 40 and 42 which span the spacing between the legs of the clamp carrier. Channels 40 and 42 are oriented opposite to one another whereby channel 40 Wil act as a guide and support for the driving motor assembly and channel 42 will act primarily as a guide for the assembly.

Motor support frame 38 also comprises a first vertical member 44 and a second substantially L-shaped member 46 which is connected to a vertical member 44 by a pivot 48. Members 44 and 46 and pivot 48 cooperate to form a motor mount carriage, member 46 being attached to motor 32 in the manner to be described below in the discussion of FIGURE 9. The motor mount carriage is movably supported in channels 40 and 42 respectively by means of rollers 50-50 and 52. Rollers 5050 and 52 are connected to member 44 by means of their respective axles 5656 and 58. Accordingly, as may most clearly be seen from FIGURES 2 and 8, the clamp tightening apparatus comprising motor 32 may be moved transversely of the rows of clamps along the horizontally spaced clamp ends by moving the motor mount carriage to the left or right, the carriage traveling along channels 40 and 42 on rollers 50-50 and 52.

As may be seen from FIGURE 2, the rotating members 28 of the clamps extend outwardly over upper channel 40 and thus lateral movement of the support carriage and motor assembly can be accomplished only if the motor 32 and its associated driving member 34 and torque reaction member 36 may be rotated t@ a position where member 36 will not strike members 28, For this purpose, aforem t c p ot 45 is rovided, Wh n it d s r d o 'slease the engagement of driving member 34 from a first clamp and to cause it to engage the next clamp to be tightened or loosened, L-shaped member 46 and the motor 32 and associated members 34 and 36 are pivoted clockwise about pivot 48 and against the tension of a counterbalancing spring 60.

Referring now to FIGURES 3 and 4, torque reaction ,member 36 comprises a pair of oppositely disposed side plates 62 and 64 which extend from a base plate 68. Base plate 68 is rigidly bolted to an extension 70 of the housing of motor 32, extension 70 containing the reduction gearing associated with the output shaft of motor 32. Side plates 62 and 64 are notched or slotted, as shown as '72 in FIGURE 3, so as to permit engagement of the motor assembly with the ends of the frames of clamps 12 as shown. The engagement of slots 72 with the end of the clamp adjacent the stationary jaw is facilitated by the bevel surfaces 72a forming flared mouths for the slots and helps to support the motor in the in-use position in addition to preventing twisting thereof and of the clamp as hereinafter described, as a reaction to the torque developed during the driving of rotating member 28 of the screw clamps.

As may best be seen from FIGURE 7, the driving member 34 for motor 32 comprises a tubular member having an internal diameter commensurate with the outer diameter of the center portion of rotating member 28 of the screw clamp. The tubular member is slotted to form a pair of oppositely disposed arcuate portions 74 and 76. The slot between portions 74 and 76 is designated to receive wings 3030' on rotating members 2 8. Accordingly, engagement of rotating member 28 of a clamp with driving member 34 will, since member 34 is affixed by suitable means to the output shaft of the reduction gearing in motor housing extension 70, cause driving of the clamp when the motor 32 is energized.

Means are provided to enable motor 32 to rotate in either direction relatively to the frame member 46. The means which permits the limited degree of rotation of the motor may be seen from FIGURES 3, 8 and 9. The housing of motor 32 has a blade 80 extending downwardly therefrom between a pair of extensions 82 on the member 46 of the motor mount carriage. Extensions 82 are bridged by a pin 84 which passes through blade 80, and between each side of blade 80 and each of extensions 82 there is disposed a spring 86. Carriage member 46 has 'a circular portion 88 which passes around the housing of motor 32, portion 88 loosely fitting in a groove defined by a member 90 which is bolted to the housing of motor 32 by means of a plurality of bolts 92-92. Accordingly, motor assembly 32 and reaction member 36 may be rotated relative to the ends of clamps 12 in order to allow engagement of slots 72 in torque reaction member' 36 with the end of the clamp, approximately 10 degrees of rotation of the motor assembly in each of oppos'ite directions, being permitted. Springs 86 will return the motor assembly and the reaction member to the center-position shown in FIGURE 8 when the assembly is disengaged from the clamp to facilitate engagement of the reaction member with the next clamp.

Returning again to FIGURE 1, air motor 32 is driven from a source of compressed air, not shown, the source being connected through a solenoid valve 93 to the motor via hoses 94 and 96 which respectively engage fittings 98 and 100 on the motor 32, a switch controlling the solenoid circuit being mounted conveniently on the motor. Means, not shown, are provided for adjusting the pres sure at the supply so that the motor will stall when the predetermined torque is developed. Accordingly, a predetermined clamping pressure will be applied to the work held between jaws 24 and 26 of clamps 12 at which time no further pressure will be applied and thus the work will not be damaged nor will twisting of the clamp occur. Energization of the motor once engagement with the clamp has been effected is accomplished by means of a switch 95 mounted on the side of the motor housing.

While a preferred embodiment has been shown and described, various modifications and substitutions may be made thereto without departing from the spirit and scope of the present invention. Accordingly, it is to be understood that the present invention has been described by way of illustration and not limitation.

We claim:

1. Clamp tightening apparatus for a clamp that has a rigid frame mounting a fixed jaw, an adjustable jaw, and means including a rotatable operating element for moving said adjustable jaw, said apparatus comprising a motor which includes a housing and a rotatable drive shaft carrying a driving member engageable with and disengageable from said operating element, a support on which said motor is mounted for limited rotation relative to the support, said support being movable to cause selectively engagement and disengagement of said driving element, respectively, with and from said operating element, and a reaction member connected to said motor housing and engageable and disen-gageable with and from said rigid frame substantially simultaneously with said engagement and disengagement of said driving member with said operating element, respectively, to prevent twisting of the clamp.

2. Apparatus for developing and individually applying torque to a plurality of adjustable devices, the plurality of adjustable devices being disposed substantially parallel to one another along a line and having portions which are rotatable relative to one another, the apparatus comprising:

an air motor having a housing and an output shaft;

a torque reaction member attached to said motor housing and being formed to engage a first portion of said adjustable means for preventing rotation of said motor relative to said adjustable means;

a driving member coupled to said air motor output shaft and adapted to engage another portion of said adjustable means for causing rotation of said other portion relative to said first portion of said adjustable means;

a first support member engaging said motor housing;

a second support member pivotably attached to said first support member; and

means mounting said second support member generally transversely of the axis of said motor output shaft when said driving member is in engagement with said adjustable means whereby disengagement of said driving member from said adjustable means may be afiected by pivoting said first support member about said second support member.

3. The apparatus of claim 2 wherein said mounting means comprises:

means supporting said second support member for movement parallel to the line defined by a plurality of adjustable means.

4. The apparatus of claim 3 wherein said mounting means further comprises:

first track means disposed parallel to said line;

a second track means disposed parallel to said first track means;

first roller means disposed in said first track means and engaging said second support means adjacent a first end thereof; and

second roller means disposed in said second track means and engaging said second support member adjacent its pivot connection to said first support member.

5. The apparatus of claim 2 further comprising:

a counterbalancing spring for the first support member extending between said first and second support members.

6. The apparatus of claim 2 wherein said first support member comprises:

a first portion which extends about the housing of said motor, said first portion loosely engaging said motor housing whereby relative rotation between said motor and said first support member may be accomplished; and

a second portion extending from said first portion and pivotably engaged by said second support member.

7. The apparatus of claim 6 wherein said motor housing has a blade extending therefrom and wherein said first support member further comprises:

a pair of projections extending from said second portion on either side of said blade;

pin means extending between said projections and passing through said blade for loosely maintaining said blade between said projections; and

centering springs disposed between said blade and each of said projections whereby a limited degree of rotation of said motor housing relative to said first support member may be achieved.

8. The apparatus of claim 6 further comprising:

a counterbalancing spring for the first support member extending between said first and second support members.

9. The apparatus of claim 8 wherein said mounting means comprises:

means supporting said second support member for movement parallel to the line defined by a plurality of adjustable means.

10. The apparatus of claim 9 wherein said mounting means further comprises:

first track means disposed parallel to said line;

a second track means disposed parallel to said first track means;

roller means disposed in said first track means and engaging said second support means adjacent a first end thereof; and

second roller means disposed in said second track means and engaging said second support member adjacent its pivot connections to said first support member.

11. The apparatus of claim 10 wherein said motor housing has a blade extending therefrom and wherein said first support member further comprises:

a pair of projections extending from said second portion on either side of said blade;

pin means extending between said projections and passmg through said blade for loosely maintaining said blade between said projections; and

centering springs disposed between said blade and said projections whereby a limited degree of rotation of said motor housing relative to said first support member may be achieved.

References Cited UNITED STATES PATENTS 1,981,499 11/1934 Francis 26956 ROBERT C. RIORDON, Primary Examiner L. GILDEN, Assistant Examiner US. Cl. X.R. 269--56, 243, 245

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 y 488 O46 D t d January 6 1969 Lloyd Quick et a1 Inventor(s) It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 3 line 38 "talk" should read torque line 8 after "plane" insert along a line Column 5 lines 28 and 29 "devices", each occurrence should read means line 30, before "having" insert each Signed and sealed this 16th day of June 1970.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. WILLIAM E. SCHUYLBR, JR. Attesting Officer Commissioner of Patents 

